It is well known in the prior art to provide a pick up truck having a cab portion for carrying passengers and a cargo box for carrying cargo. The cargo box typically includes wheel covers which decrease the available width of the cargo box at the lower portion of the box. It is also known in the prior art that wider loads may be carried in the cargo box by providing one or more planar members, such as boards, which assist in carrying a wider load above the wheel covers in the cargo box.
It is also known in the prior art to provide a hole or passage the cab portion and the cargo box portion for carrying a somewhat longer load on the floor of the truck. However, this arrangement has the shortcoming of not being able to accommodate wider loads. In addition, these configurations are not well-adapted for carrying passengers when not in use for carrying cargo. Other passages or openings have been provided between cab portions and cargo boxes, however, these configurations are concerned with the passing through or seating of passengers and are not suited for carrying longer and wider cargo loads.
As the popularity of trucks increases, it has become desirable to provide trucks that have rearward extended cab portions suitable for carrying more than three passengers. However, this reduces the load carrying capacity of the cargo boxes.